Gas-cushion vehicles

ABSTRACT

A gas-cushion vehicle has a gas-cushion supply duct in its hull through which a lift fan supplies gas under pressure to the vehicle&#39;&#39;s gas-cushion. The duct contains a valve formed from segments of flexible material which allow gas to flow from the lift fan to the gas-cushion but automatically invert to obstruct reverse flow of gas from the gas-cushion through an inoperative lift fan.

United States Patent [191 Dyke [ GAS-CUSHION VEHICLES [75] Inventor: Raymond William Dyke,

Southampton, England [73] Assignee: Vosper Limited, Portsmouth,

England [22] Filed: Feb. 23, 1972 [21] Appl. No.2 228,774

Related US. Application Data [63] Continuation of Ser. No, 689, Jan. 5, I970,

abandoned.

[30] Foreign Application Priority Data Jan. 8, 1969 Great Britain 1172/69 [52] US. Cl 180/116, 137/525.1, 180/122, 180/128 [51] lint. Cl. B60r 1/02 [58] Field of Search 180/116, 117, 118, 120, ISO/121,122,124,125,127,128, 129; 137/5251, 493, 525.3, 525

[56] References Cited UNITED STATES PATENTS 2,358,143 9/1944 Castor 137/493 X 2,630,178 3/1953 Brown 2,926,686 3/1960 Ghreen 137/517 X 2,941,544 6/1960 Peras 1. 137/493 2,958,487 11/1960 Fraebel 244/138 R 3,050,146 8/1962 Crim 180/116 X 3,106,260 10/1963 Bollum t 180/116 3,181,636 5/1965 Cockcrell 180/118 3,425,505 2/1969 Jones 180/118 3,443,659 5/1969 Moore ct a1. 180/118 3,552,519 1/1971 Wren 1811/124 FOREIGN PATENTS OR APPLICATIONS 559,321 3/1957 ltaly 137/5253 Primary ExaminerDavid Schonberg Assistant ExaminerJohn P. Silverstrim Attorney, Agent, or FirmNorris & Bateman [5 7 ABSTRACT A gas-cushion vehicle has a gas-cushion supply duct in its hull through which a lift fan supplies gas under pressure to the vehicles gas-cushion. The duct contains a valve formed from segments of flexible material which allow gas to flow from the lift fan to the gascushion but automatically invert to obstruct reverse flow of gas from the gas-cushion through an inoperative lift fan.

3 Claims, 4 Drawing Figures SHEET 10? 2 PATENIEBUCT 1 51974 INVENTOR RAYMOND WILLIAM DYKE PATENTEDUBT 1 51914 s-,&41.43a sum 2 0r 2 INVENTOR RAYMOND WILLIAM DYKE YWSM i1 gdliimuu AT TO R N E Y GAS-CUSHION VEHICLES This is a continuation of application Ser. No. 689, filed Jan. 5, 1970, now abandoned.

BACKGROUND OF THE INVENTION The invention relates to vehicles which are wholly or partially supported by at least one cushion of pressurised gas, and more particularly to improvements in ducts through which gas under pressure passes to supply the cushion or cushions.

It is usual for the gas to be pressurised by one or more lift fans and supplied through a duct or ducts to the or each cushion. If the lift fan or one of the lift fans fails it is desirable to prevent the loss of gas from said cushion or cushions by reverse flow through the inoperative lift fan.

SUMMARY OF THE INVENTION The object of the invention is to provide a simple valve in the duct to minimise the loss of gas from the cushion or cushions by such reverse flow.

According to the invention, a vehicle which is wholly or partially supported by at least one cushion of pressurised gas comprises a hull, means for supplying gas under pressure to the or each cushion by way of at least one duct in said hull and valve means in the or each duct formed of one or more segments of flexible material.

DESCRIPTION OF THE INVENTION.

A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings of which:

FIG. 1 is a diagrammatic part sectional side elevation of an air-cushion vehicle;

FIG. 2 is a part sectional side elevation of an aircushion supply duct in the air-cushion vehicle;

FIG. 3 is a part sectional plan view of the air-cushion supply duct; and

FIG. 4 is a perspective view of part of the air-cushion supply duct.

Referring now to the drawings, an air-cushion supply duct in an air-cushion vehicles hull ll connects a lift fan 7 to an air-cushion 8 confined by a skirt 9. Fabric segments 12 coated with rubber or plastics material are pivotally mounted in two rows in the duct 10. Each segment 12 is connected by a cord 13, which passes through an eyelet 14 in the segment 12, to a pin 15 in the duct 10 and also by two cords 16, which pass through two eyelets 17 in the segment 12, to two pins 18 mounted on a bar 19. The bar 19 is attached at its ends to the walls of the duct 10. As shown in the drawings a corner of each segment 12 is pivoted to a duct wall at pin 15 and the other two corners are pivoted on a common axis at pins 18.

In operation, air under pressure flows through the duct 10 in the direction of the arrow A, that is to say from the lift fan 7 to the air-cushion 8, and the segments 12 take up the position shown in full lines in the drawings and thus offer little resistance to the flow of air. If the lift fan fails and air begins to flow in the reverse direction the segments 12 automatically pivot about the pins 15, 18 and invert to take up the position shown in broken lines in FIG. 2 and form a seal across the duct 10 minimising said reverse flow.

- What I claim is:

1. A vehicle supported by a cushion of pressurized gas comprising a hull, gas supply means for supplying gas under pressure to said cushion, a duct in said hull connecting said gas supply means with said cushion, and check valve means in said duct actuated by reverse gas flow from said cushion into said duct to a close position to at least partially seal said duct against said reverse gas flow upon failure of said gas supply means, said check valve means including at least one triangular valve segment of flexible material pivotally connected at all three corners to the hull, two of said corners being adjacent and substantially aligned to provide a common pivot axis therefor, said segment being movable between a normal valve open position during the time gas under pressure is supplied to said cushion and an inverted closed valve position in response to said reverse gas flow.

2. A vehicle according to claim 1, wherein said check valve means comprises two rows of said segments pivotally mounted alongside each other and extending across the duct.

3. A vehicle according to claim 2, wherein the segments of the respective rows each have one corner pivotally connected to a wall of the duct and said two adjacent corners pivotally connected to a common fixed member within the duct. 

1. A vehicle supported by a cushion of pressurized gas comprising a hull, gas supply means for supplying gas under pressure to said cushion, a duct in said hull connecting said gas supply means with said cushion, and check valve means in said duct actuated by reverse gas flow from said cushion into said duct to a close position to at least partially seal said duct against said reverse gas flow upon failure of said gas supply means, said check valve means including at least one triangular valve segment of flexible material pivotally connected at all three corners to the hull, two of said corners being adjacent and substantially aligned to provide a common pivot axis therefor, said segment being movable between a normal valve open position during the time gas under pressure is supplied to said cushion and an inverted closed valve position in response to said reverse gas flow.
 2. A vehicle according to claim 1, wherein said check valve means comprises two rows of said segments pivotally mounted alongside each other and extending across the duct.
 3. A vehicle according to claim 2, wherein the segments of the respective rows each have one corner pivotally connected to a wall of the duct and said two adjacent corners pivotally connected to a common fixed member within the duct. 